#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int average(int x, int y)
{
	return (x + (y-x )/ 2);
}
int main()
{
	int x = 0;
	int y = 0;
	scanf("%d %d", &x, &y);
	int ret=average(x, y);
	printf("%d\n", ret);
	return 0;
}